This European Standard specifies traceable calibration methods of black-standard thermometers (BST), white-standard thermometers (WST), black-panel thermometers (BPT) and white-panel thermometers (WPT) for use in natural and artificial weathering: ¾ð method A, a contact method, uses a traceable calibrated resistance standard thermometer ¾ð method B, a contactless method, uses a traceable calibrated pyrometer. A basic design of types of the thermometers is described in EN ISO 4892 1. NOTE 1 Historically method A has been used for weathering applications for many years. Method B has been developed recently. Both methods are qualified for weathering applications. Both methods may provide different calibration results which are not interchangeable. NOTE 2 Annex A gives information on the characteristics of BST/WST and BPT/WPT.